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					<h1>CodeIgniter User Guide Version 2.0.3</h1>
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		<h1>Database Configuration</h1>

		<p>
			CodeIgniter has a config file that lets you store your database
			connection values (username, password, database name, etc.). The
			config file is located at
			<samp>application/config/database.php</samp>
			. You can also set database connection values for specific <a
				href="../libraries/config.html">environments</a> by placing <strong>database.php</strong>
			it the respective environment config folder.
		</p>

		<p>The config settings are stored in a multi-dimensional array
			with this prototype:</p>

		<code>
			$db['default']['hostname'] = "localhost";<br />
			$db['default']['username'] = "root";<br />
			$db['default']['password'] = "";<br /> $db['default']['database'] =
			"database_name";<br /> $db['default']['dbdriver'] = "mysql";<br />
			$db['default']['dbprefix'] = "";<br /> $db['default']['pconnect'] =
			TRUE;<br /> $db['default']['db_debug'] = FALSE;<br />
			$db['default']['cache_on'] = FALSE;<br /> $db['default']['cachedir']
			= &quot;&quot;;<br /> $db['default']['char_set'] = "utf8";<br />
			$db['default']['dbcollat'] = "utf8_general_ci";<br />
			$db['default']['swap_pre'] = "";<br /> $db['default']['autoinit'] =
			TRUE;<br /> $db['default']['stricton'] = FALSE;
		</code>

		<p>The reason we use a multi-dimensional array rather than a more
			simple one is to permit you to optionally store multiple sets of
			connection values. If, for example, you run multiple environments
			(development, production, test, etc.) under a single installation,
			you can set up a connection group for each, then switch between
			groups as needed. For example, to set up a "test" environment you
			would do this:</p>

		<code>
			$db['test']['hostname'] = "localhost";<br /> $db['test']['username']
			= "root";<br /> $db['test']['password'] = "";<br />
			$db['test']['database'] = "database_name";<br />
			$db['test']['dbdriver'] = "mysql";<br /> $db['test']['dbprefix'] =
			"";<br /> $db['test']['pconnect'] = TRUE;<br />
			$db['test']['db_debug'] = FALSE;<br /> $db['test']['cache_on'] =
			FALSE;<br /> $db['test']['cachedir'] = &quot;&quot;;<br />
			$db['test']['char_set'] = "utf8";<br /> $db['test']['dbcollat'] =
			"utf8_general_ci";<br /> $db['test']['swap_pre'] = "";<br />
			$db['test']['autoinit'] = TRUE;<br /> $db['test']['stricton'] =
			FALSE;
		</code>


		<p>Then, to globally tell the system to use that group you would
			set this variable located in the config file:</p>

		<code>$active_group = "test";</code>

		<p>Note: The name "test" is arbitrary. It can be anything you
			want. By default we've used the word "default" for the primary
			connection, but it too can be renamed to something more relevant to
			your project.</p>

		<h3>Active Record</h3>

		<p>
			The <a href="active_record.html">Active Record Class</a> is globally
			enabled or disabled by setting the $active_record variable in the
			database configuration file to TRUE/FALSE (boolean). If you are not
			using the active record class, setting it to FALSE will utilize fewer
			resources when the database classes are initialized.
		</p>

		<code>$active_record = TRUE;</code>

		<p class="important">
			<strong>Note:</strong> that some CodeIgniter classes such as Sessions
			require Active Records be enabled to access certain functionality.
		</p>

		<h3>Explanation of Values:</h3>

		<ul>
			<li><strong>hostname</strong> - The hostname of your database
				server. Often this is "localhost".</li>
			<li><strong>username</strong> - The username used to connect to
				the database.</li>
			<li><strong>password</strong> - The password used to connect to
				the database.</li>
			<li><strong>database</strong> - The name of the database you
				want to connect to.</li>
			<li><strong>dbdriver</strong> - The database type. ie: mysql,
				postgres, odbc, etc. Must be specified in lower case.</li>
			<li><strong>dbprefix</strong> - An optional table prefix which
				will added to the table name when running <a
				href="active_record.html">Active Record</a> queries. This permits
				multiple CodeIgniter installations to share one database.</li>
			<li><strong>pconnect</strong> - TRUE/FALSE (boolean) - Whether
				to use a persistent connection.</li>
			<li><strong>db_debug</strong> - TRUE/FALSE (boolean) - Whether
				database errors should be displayed.</li>
			<li><strong>cache_on</strong> - TRUE/FALSE (boolean) - Whether
				database query caching is enabled, see also <a href="caching.html">Database
					Caching Class</a>.</li>
			<li><strong>cachedir</strong> - The absolute server path to your
				database query cache directory.</li>
			<li><strong>char_set</strong> - The character set used in
				communicating with the database.</li>
			<li><strong>dbcollat</strong> - The character collation used in
				communicating with the database.
				<p class="important">
					<strong>Note:</strong> For MySQL and MySQLi databases, this setting
					is only used as a backup if your server is running PHP &lt; 5.2.3
					or MySQL &lt; 5.0.7. There is an incompatibility in PHP with
					mysql_real_escape_string() which can make your site vulnerable to
					SQL injection if you are using a multi-byte character set and are
					running versions lower than these. Sites using Latin-1 or UTF-8
					database character set and collation are unaffected.
				</p></li>
			<li><strong>swap_pre</strong> - A default table prefix that
				should be swapped with <var>dbprefix</var>. This is useful for
				distributed applications where you might run manually written
				queries, and need the prefix to still be customizable by the end
				user.</li>
			<li><strong>autoinit</strong> - Whether or not to automatically
				connect to the database when the library loads. If set to false, the
				connection will take place prior to executing the first query.</li>
			<li><strong>stricton</strong> - TRUE/FALSE (boolean) - Whether
				to force "Strict Mode" connections, good for ensuring strict SQL
				while developing an application.</li>
			<li><strong>port</strong> - The database port number. To use
				this value you have to add a line to the database config array.<code>$db['default']['port']
					= 5432;</code>
		</ul>

		<p class="important">
			<strong>Note:</strong> Depending on what database platform you are
			using (MySQL, Postgres, etc.) not all values will be needed. For
			example, when using SQLite you will not need to supply a username or
			password, and the database name will be the path to your database
			file. The information above assumes you are using MySQL.
		</p>



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